Adrenal Glands | Johns Hopkins Medicine Health Library Adrenal Glands: What You Need to Know Adrenal glands, also known as suprarenal glands, are small, triangular-shaped glands located on top of both kidneys. Adrenal glands produce hormones that help regulate your metabolism, immune system, blood pressure, response to stress and other essential functions. Adrenal glands are composed of two parts — the cortex and the medulla — which are each responsible for producing different hormones. When adrenal glands don’t produce enough hormones, this can lead to adrenal insufficiency (Addison’s disease). Adrenal glands may develop nodules that can be benign or malignant. These nodules may produce excessive amounts of certain hormones leading to various health issues. Anatomy of the Adrenal Glands An adrenal gland is made of two main parts: The adrenal cortex is the outer region and also the largest part of an adrenal gland. It is divided into three separate zones: zona glomerulosa, zona fasciculata and zona reticularis. Each zone is responsible for producing specific hormones. The adrenal medulla is located inside the adrenal cortex in the center of an adrenal gland. It produces several “stress hormones,” including adrenaline.

The adrenal cortex and adrenal medulla are enveloped in an adipose capsule that forms a protective layer around an adrenal gland. Hormones of the Adrenal Glands The role of the adrenal glands in your body is to release certain hormones directly into the bloodstream. Many of these hormones have to do with how the body responds to stress, and some are vital to existence. Both parts of the adrenal glands — the adrenal cortex and the adrenal medulla — perform distinct and separate functions. Each zone of the adrenal cortex secretes a specific hormone. The key hormones produced by the adrenal cortex include: Cortisol Cortisol is a glucocorticoid hormone produced by the zona fasciculata that plays several important roles in the body. It helps control the body’s use of fats, proteins and carbohydrates; suppresses inflammation; regulates blood pressure; increases blood sugar; and can also decrease bone formation. This hormone also controls the sleep/wake cycle. It is released during times of stress to help your body get an energy boost and better handle an emergency situation. How Adrenal Glands Work to Produce Cortisol Adrenal glands produce hormones in response to signals from the hypothalamus and the pituitary gland in the brain.

For example, for the adrenal gland to produce cortisol: The hypothalamus produces corticotropin-releasing hormone (CRH) that stimulates the pituitary gland to secrete adrenocorticotropin hormone (ACTH). The ACTH then stimulates the adrenal glands to make and release cortisol hormones into the blood. Normally, both the hypothalamus and the pituitary gland can sense whether the blood has the right amount of cortisol in it. If there is too much or too little cortisol, these glands respectively change the amount of CRH and ACTH that gets released. Excess cortisol production can occur from nodules in the adrenal gland or excess production of ACTH from a tumor in the pituitary gland or other source. Aldosterone This mineralocorticoid hormone produced by the zona glomerulosa plays a central role in regulating blood pressure and certain electrolytes (sodium and potassium). Aldosterone sends signals to the kidneys, resulting in the kidneys absorbing more sodium into the bloodstream and releasing potassium into the urine. This means that aldosterone also helps regulate the blood pH by controlling the levels of electrolytes in the blood.

DHEA and Androgenic Steroids These hormones produced by the zona reticularis are weak male hormones. They are precursor hormones that are converted in the ovaries into female hormones (estrogens) and in the testes into male hormones (androgens). However, estrogens and androgens are produced in much larger amounts by the ovaries and testes. Epinephrine (Adrenaline) and Norepinephrine (Noradrenaline) The adrenal medulla, the inner part of an adrenal gland, controls hormones that help you cope with physical and emotional stress. The main hormones secreted by the adrenal medulla include epinephrine (adrenaline) and norepinephrine (noradrenaline), which have similar functions. Among other things, these hormones are capable of increasing the heart rate and force of heart contractions, increasing blood flow to the muscles and brain, relaxing smooth muscles, and assisting in sugar metabolism. They also control the squeezing of the blood vessels (vasoconstriction), helping maintain blood pressure and increasing it in response to stress.

Like several other hormones produced by the adrenal glands, epinephrine and norepinephrine are often activated in stressful situations when your body needs additional resources and energy to endure unusual strain. Adrenal Gland Disorders The two common ways in which adrenal glands cause health issues are by producing too little or too much of certain hormones, which leads to hormonal imbalances. These abnormalities of the adrenal function can be caused by various diseases of the adrenal glands or the pituitary gland. Adrenal Insufficiency Adrenal insufficiency is a rare disorder. It may be caused by disease of the adrenal glands (primary adrenal insufficiency, Addison’s disease) or by diseases in the hypothalamus or the pituitary (secondary adrenal insufficiency). It is the opposite of Cushing syndrome and is characterized by low levels of cortisol (and aldosterone in the primary form). The symptoms include weight loss, poor appetite, nausea and vomiting, fatigue, darkening of skin (only in primary adrenal insufficiency), abdominal pain, etc. The causes of primary adrenal insufficiency may include autoimmune disorders, fungal and other infections, cancer (rarely), and genetic factors.

Although adrenal insufficiency usually develops over time, it can also appear suddenly as an acute adrenal failure (adrenal crisis). It has similar symptoms, but the consequences are more serious, including coma, shock and seizures. These may develop if the condition is left untreated. Congenital Adrenal Hyperplasia Adrenal insufficiency can also result from a genetic disorder called congenital adrenal hyperplasia. Children who are born with this disorder are missing an essential enzyme necessary to produce cortisol, aldosterone or both. At the same time, they often experience excess of androgen, which may lead to male characteristics in girls and precocious puberty in boys. Congenital adrenal hyperplasia can remain undiagnosed for years depending on the severity of the enzyme deficiency. In more severe cases, infants may suffer from dehydration, vomiting and failure to thrive. Overactive Adrenal Glands Sometimes, adrenal glands may develop nodules that produce too much of certain hormones. Nodules 4 centimeters or larger and nodules that show certain features on imaging may be cancerous. Both benign and cancerous nodules may produce excessive amounts of certain hormones, which often is referred to as an overactive adrenal gland .

Excess of Cortisol: Cushing Syndrome Cushing syndrome results from excessive production of cortisol from the adrenal glands. The symptoms may include weight gain and fatty deposits in certain areas of the body, such as the face, below the back of the neck and in the abdomen; thinning arms and legs; purple stretch marks on the abdomen; facial hair; fatigue; muscle weakness; easily bruised skin; high blood pressure; diabetes; and other health issues. Excess cortisol production can also be triggered by overproduction of ACTH by a benign tumor in the pituitary gland. This is known as Cushing Disease. Another common cause of Cushing syndrome is excessive and prolonged consumption of external steroids, such as prednisone or dexamethasone, which are prescribed to treat many autoimmune or inflammatory diseases (e.g., lupus, rheumatoid arthritis, asthma, inflammatory bowel disease, multiple sclerosis, etc.) Excess of Aldosterone: Hyperaldosteronism Hyperaldosteronism results from overproduction of aldosterone from one or both adrenal glands. This is characterized by increase in blood pressure that often requires many medications to control. Some people can develop low potassium levels in the blood, which can cause muscle aches, weakness and spasms.

When the cause is a benign tumor in one adrenal gland, the disease is called Conn syndrome. Excess of Adrenaline or Noradrenaline: Pheochromocytoma Pheochromocytoma is a tumor that results in excess production of adrenaline or noradrenaline by the adrenal medulla that often happens in bursts. Occasionally, neural crest tissue, which is similar to the adrenal medulla, may be the cause of overproduction of these hormones. This condition is called a paraganglioma. Pheochromocytomas may cause persistent or sporadic high blood pressure that may be difficult to control with regular medications. Other symptoms include headaches, sweating, tremors, anxiety and rapid heartbeat. Some people are genetically predisposed to developing this type of tumor. Adrenal Cancer Malignant adrenal tumors (adrenal cancer), such as adrenocortical carcinoma, are rare and often have spread to other organs and tissues by the time they are diagnosed. These tumors tend to grow fairly large and can reach several inches in diameter. Adrenal cancer may cause adrenal glands to produce excess of one or more hormones accompanied by corresponding symptoms, as listed above.

You may also experience abdominal pain or flank pain and a feeling of fullness if the adrenal tumor gets very large. Not all cancers found in adrenal glands start there. Most adrenal cancers are secondary cancers that start elsewhere in the body and spread to the adrenal glands. Experience Our Care An Overview of the Adrenal Glands - Beyond Fight or Flight An Overview of the Adrenal Glands Beyond Fight or Flight Written by Robert M. Sargis MD, PhD Adrenal Gland Essentials The adrenal glands are two glands that sit on top of your kidneys that are made up of two distinct parts. The adrenal cortex—the outer part of the gland—produces hormones that are vital to life, such as cortisol (which helps regulate metabolism and helps your body respond to stress) and aldosterone (which helps control blood pressure). The adrenal medulla—the inner part of the gland—produces nonessential (that is, you don’t need them to live) hormones, such as adrenaline (which helps your body react to stress). When you think of the adrenal glands (also known as suprarenal glands), stress might come to mind.

And rightly so—the adrenal glands are arguably best known for secreting the hormone adrenaline, which rapidly prepares your body to spring into action in a stressful situation. But the adrenal glands contribute to your health even at times when your body isn’t under extreme stress. In fact, they release hormones that are essential for you to live. Anatomy of the Adrenal Glands The adrenal glands are two, triangular-shaped organs that measure about 1.5 inches in height and 3 inches in length. They are located on top of each kidney. Their name directly relates to their location (ad—near or at; renes—kidneys). Each adrenal gland is comprised of two distinct structures—the outer part of the adrenal glands is called the adrenal cortex. The inner region is known as the adrenal medulla. Hormones of the Adrenal Glands The adrenal cortex and the adrenal medulla have very different functions. One of the main distinctions between them is that the hormones released by the adrenal cortex are necessary for life; those secreted by the adrenal medulla are not. Adrenal Cortex Hormones The adrenal cortex produces two main groups of corticosteroid hormones—glucocorticoids and mineralcorticoids.

The release of glucocorticoids is triggered by the hypothalamus and pituitary gland . Mineralcorticoids are mediated by signals triggered by the kidney. When the hypothalamus produces corticotrophin-releasing hormone (CRH), it stimulates the pituitary gland to release adrenal corticotrophic hormone (ACTH). These hormones, in turn, alert the adrenal glands to produce corticosteroid hormones. Glucocorticoids released by the adrenal cortex include: Hydrocortisone: Commonly known as cortisol, it regulates how the body converts fats, proteins, and carbohydrates to energy. It also helps regulate blood pressure and cardiovascular function. Corticosterone: This hormone works with hydrocortisone to regulate immune response and suppress inflammatory reactions. The principle mineralcorticoid is aldosterone, which maintains the right balance of salt and water while helping control blood pressure. There is a third class of hormone released by the adrenal cortex, known as sex steroids or sex hormones. The adrenal cortex releases small amounts of male and female sex hormones. However, their impact is usually overshadowed by the greater amounts of hormones (such as estrogen and testosterone) released by the ovaries or testes .

Adrenal Medulla Hormones Unlike the adrenal cortex, the adrenal medulla does not perform any vital functions. That is, you don’t need it to live. But that hardly means the adrenal medulla is useless. The hormones of the adrenal medulla are released after the sympathetic nervous system is stimulated, which occurs when you’re stressed. As such, the adrenal medulla helps you deal with physical and emotional stress. You can learn more by reading a SpineUniverse article about the sympathetic nervous system . You may be familiar with the fight-or-flight response—a process initiated by the sympathetic nervous system when your body encounters a threatening (stressful) situation. The hormones of the adrenal medulla contribute to this response. Hormones secreted by the adrenal medulla are: Epinephrine: Most people know epinephrine by its other name—adrenaline. This hormone rapidly responds to stress by increasing your heart rate and rushing blood to the muscles and brain. It also spikes your blood sugar level by helping convert glycogen to glucose in the liver. (Glycogen is the liver’s storage form of glucose.) Norepinephrine: Also known as noradrenaline, this hormone works with epinephrine in responding to stress.

However, it can cause vasoconstriction (the narrowing of blood vessels). This results in high blood pressure. Disorders and Diseases of the Adrenal Glands There are multiple reasons why the adrenal glands might not work as they should. The problem could be with the adrenal gland itself, or the root cause may be due to a defect in another gland. Below are the most common disorders and diseases of the adrenal glands: Addison’s disease: This rare disorder may affect anyone at any age. It develops when the adrenal cortex fails to produce enough cortisol and aldosterone. To learn more, read our article about Addison's Disease . Adrenal cancer: Adrenal cancer is an aggressive cancer, but it’s very rare. Malignant adrenal tumors are rarely confined to the adrenal glands—they tend to spread to other organs and cause adverse changes within the body because of the excess hormones they produce. To learn more, read our article about adrenal cancer . Cushing’s syndrome: Cushing’s syndrome is an uncommon condition that is essentially the opposite of Addison’s disease. It is caused by overproduction of the hormone cortisol. There are a variety of causes of this disorder—a tumor in the adrenal gland or pituitary gland could be to blame.

To learn more, read our article about Cushing's syndrome . Congenital adrenal hyperplasia: This genetic disorder is characterized by low levels of cortisol. It’s common for people with congenital adrenal hyperplasia to have additional hormone problems such as low levels of aldosterone (which maintains a balance of water and salt). The adrenal glands have a multi-functional role in the endocrine system. The two very different parts of these glands, the medulla and cortex, regulate and maintain many of your internal processes—from metabolism to the fight-or-flight response. adrenal cortex secretes three types of steroids or - ECON - 102 Adrenal cortex secretes three types of steroids or SCHOOL adrenal cortex secretes three types of steroids or corticosteroids § Glucosteroids § cortisol - aids in metabolism and also aids the body during stress § Mineralcorticoids § aldosterone - regulates electrolyte levels § Sex hormones § Androgens (testosterone) and estrogens § Influence sex characteristics This preview has intentionally blurred sections. Sign up to view the full version.

Glands and Hormones Adrenal Glands Adrenal medulla - inner portion of the gland • epinephrine and norepinephrine - aid body during stress by raising heart rate, blood pressure, and respiration This preview has intentionally blurred sections. Sign up to view the full version. View Full Document Glands and Hormones Islets of Langerhans [3] Endocrine cells inside the pancreas [1], which is located partly behind the stomach [2] • insulin - regulates blood glucose levels • When blood glucose rises, insulin is released to facilitate entrance of glucose into body cells and Islets of Langerhans Hormones and Actions Pancreas (islet cells) Glucagon Insulin Lowers blood sugar (glucose to glycogen) Raises blood sugar (glycogen to glucose) This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Glands and Hormones Ovaries Female reproductive glands attached to the uterus • estrogen and progesterone - affect the development of female sexual organs and secondary sexual characteristics; regulate menstrual cycle and pregnancy Glands and Hormones Testes Male reproductive glands located in the scrotum • testosterone - affects development of sexual organs in males and secondary sexual characteristics This preview has intentionally blurred sections. Sign up to view the full version. Combining Forms • acr/o • aden/o • adren/o, adrenal/o • calc/i • cortic/o • crin/o • dips/o • endocrin/o • gluc/o, glucos/o, glyc/o, glycos/o Combining Forms • hormon/o • kal/i • natr/i • pancreat/o • parathyroid/o • thym/o • thyr/o, thyroid/o This preview has intentionally blurred sections. Sign up to view the full version. Suffixes/ Prefixes -megaly -oid -penia eu- hyper- hypo- poly- Hypogonadism Thyroiditis Hypercalciuria Polydipsia Glycosuria This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Adenomegaly Endocrinopathy Thyroparathyroide ctomy Thyroidotomy Adjectives and Other Related Terms endogenous - produced inside the body exogenous - produced outside of the body metabolism - all physical and chemical changes that occur in tissue This preview has intentionally blurred sections. Sign up to view the full version. View Full Document Abnormal Conditions of the Thyroid Gland Hormones secreted by the Thyroid Gland Hormones secreted by the Thyroid Gland Thyroxine (T4) - regulates metabolism Triiodothyronine (T3) - regulates metabolism Calcitonin – stimulates calcium to leave the blood and enter the bones This preview has intentionally blurred sections. Sign up to view the full version. View Full Document Abnormal Conditions Hypersecretion Hyperthyroidism • Most common form is Graves disease (autoimmune) s Increased metabolism, increase in heart rate, higher body temperature, hyperactivity, exophthalmos (protrusion of eyeballs) • Treatment s Antithyroid drugs to reduce amount of thyroid hormone produced; radioactive iodine to destroy overactive glandular tissue This preview has intentionally blurred sections. Sign up to view the full version.

Adrenal Glands - Health Encyclopedia - University of Rochester Medical Center The Adrenal Glands Anatomy of the adrenal glands Adrenal glands, also called suprarenal glands, are small, triangular glands located on top of both kidneys. An adrenal gland is made of two parts. The outer region is called the adrenal cortex and the inner region is called the adrenal medulla. Both parts of the adrenal glands--the adrenal cortex and the adrenal medulla--have distinct functions. Function of the adrenal glands Adrenal glands interact with the hypothalamus and pituitary gland in the brain. For example, for the adrenal gland to make corticosteroid hormones: The hypothalamus produces corticotropin-releasing hormone (CRH). This stimulates the pituitary gland to produce adrenocorticotropin hormone (ACTH). The ACTH stimulates the adrenal glands to make and release corticosteroid hormones into the blood. Both the hypothalamus and the pituitary gland can sense whether the blood has the right amount of an adrenal hormone (cortisol) in it. If there is too much or too little cortisol, these glands change the amount of CRH and ACTH they release. What is the adrenal cortex?

The adrenal cortex secretes hormones that have an effect on the body's metabolism, on chemicals in the blood, and on certain body characteristics. The adrenal cortex secretes hormones into the bloodstream. The hormones made by the adrenal cortex include: Cortisol. This hormone helps control the body's use of fats, proteins, and carbohydrates. It suppresses inflammatory reactions in the body and also affects the immune system. Cortisol is needed to maintain blood pressure in times of stress. Aldosterone. This hormone regulates the level of sodium and potassium in the body. It also helps maintain blood volume and blood pressure. Aldosterone is regulated by complex feedback mechanisms involving sodium and potassium levels as well as blood volume. Androgen hormones. These hormones are converted elsewhere in the body to female hormones (estrogens) and male hormones (androgens). But, these steroid hormones are made in much larger amounts by the ovaries (estrogen) in women and testes (androgens) in men. What is the adrenal medulla? The adrenal medulla is the inner part of the adrenal gland. It helps a person cope with physical and emotional stress. The adrenal medulla secretes these hormones: Epinephrine (also called adrenaline).

This hormone helps the body respond to a stressful situation by increasing the heart rate and force of heart contractions. It also directs blood flow to the muscles and brain, causes relaxation of smooth muscles, and helps convert glycogen to glucose in the liver, and other activities. Norepinephrine (also called noradrenaline). This hormone leads to squeezing of the blood vessels (vasoconstriction). This helps maintain blood pressure and increases it in response to sudden stress. Medical Reviewers: Holloway, Beth Greenblatt, RN, M.Ed. Hurd, Robert, MD Endocrine System Endocrine System Sistema endócrino Although we rarely think about them, the glands of the endocrine system and the hormones they release influence almost every cell, organ, and function of our bodies. The endocrine system is instrumental in regulating mood, growth and development, tissue function, and metabolism, as well as sexual function and reproductive processes. In general, the endocrine system is in charge of body processes that happen slowly, such as cell growth. Faster processes like breathing and body movement are controlled by the nervous system . But even though the nervous system and endocrine system are separate systems, they often work together to help the body function properly.

About the Endocrine System The foundations of the endocrine system are the hormones and glands. As the body's chemical messengers, hormones transfer information and instructions from one set of cells to another. Although many different hormones circulate throughout the bloodstream, each one affects only the cells that are genetically programmed to receive and respond to its message. Hormone levels can be influenced by factors such as stress, infection, and changes in the balance of fluid and minerals in blood . A gland is a group of cells that produces and secretes, or gives off, chemicals. A gland selects and removes materials from the blood, processes them, and secretes the finished chemical product for use somewhere in the body. Some types of glands release their secretions in specific areas. For instance, exocrine glands, such as the sweat and salivary glands, release secretions in the skin or inside of the mouth. Endocrine glands, on the other hand, release more than 20 major hormones directly into the bloodstream, where they can move to cells in other parts of the body.

continue Parts of the Endocrine System The major glands that make up the human endocrine system are the hypothalamus, pituitary, thyroid, parathyroids, adrenals, pineal body, and the reproductive glands, which include the ovaries and testes. The pancreas is also part of this hormone-secreting system, even though it is also associated with the digestive system because it also produces and secretes digestive enzymes. Although the endocrine glands are the body's main hormone producers, some non-endocrine organs — such as the brain, heart, lungs, kidneys, liver, thymus, skin, and placenta — also produce and release hormones. The Hypothalamus The hypothalamus, a collection of specialized cells that is located in the lower central part of the brain, is the primary link between the endocrine and nervous systems. Nerve cells in the hypothalamus control the pituitary gland by producing chemicals that either stimulate or suppress hormone secretions from the pituitary. Although it is no bigger than a pea, the pituitary gland, located at the base of the brain just beneath the hypothalamus, is considered the most important part of the endocrine system.

It's often called the "master gland" because it makes hormones that control several other endocrine glands. The production and secretion of pituitary hormones can be influenced by factors such as emotions and seasonal changes. To accomplish this, the hypothalamus relays information sensed by the brain (such as environmental temperature, light exposure patterns, and feelings) to the pituitary. previous continue The Pituitary Gland The tiny pituitary gland is divided into two parts: the anterior lobe and the posterior lobe. The anterior lobe regulates the activity of the thyroid, adrenals, and reproductive glands. Among the hormones it produces are: growth hormone, which stimulates the growth of bone and other body tissues and plays a role in the body's handling of nutrients and minerals prolactin, which activates milk production in women who are breastfeeding thyrotropin, which stimulates the thyroid gland to produce thyroid hormones corticotropin, which stimulates the adrenal gland to produce certain hormones The pituitary also secretes endorphins, chemicals that act on the nervous system to reduce sensitivity to pain. In addition, the pituitary secretes hormones that signal the ovaries and testes to make sex hormones.

The pituitary gland also controls ovulation and the menstrual cycle in women. The posterior lobe of the pituitary releases antidiuretic hormone, which helps control body water balance through its effect on the kidneys and urine output; and oxytocin, which triggers the contractions of the uterus that occur during labor. The Thyroid and Parathyroids The thyroid, located in the front part of the lower neck, is shaped like a bow tie or butterfly and produces the thyroid hormones thyroxine and triiodothyronine. These hormones control the rate at which cells burn fuels from food to produce energy. As the level of thyroid hormones increases in the bloodstream, so does the speed at which chemical reactions occur in the body. Thyroid hormones also play a key role in bone growth and the development of the brain and nervous system in children. The production and release of thyroid hormones is controlled by thyrotropin, which is secreted by the pituitary gland. Attached to the thyroid are four tiny glands that function together called the parathyroids. They release parathyroid hormone, which regulates the level of calcium in the blood with the help of calcitonin, which is produced in the thyroid.

previous continue The Adrenal Glands The body has two triangular adrenal glands, one on top of each kidney. The adrenal glands have two parts, each of which produces a set of hormones and has a different function. The outer part, the adrenal cortex, produces hormones called corticosteroids that influence or regulate salt and water balance in the body, the body's response to stress, metabolism, the immune system, and sexual development and function. The inner part, the adrenal medulla, produces catecholamines, such as epinephrine. Also called adrenaline, epinephrine increases blood pressure and heart rate when the body experiences stress. (Epinephrine injections are often used to counteract a severe allergic reaction.) The Pineal Gland and Gonads The pineal body, also called the pineal gland, is located in the middle of the brain. It secretes melatonin, a hormone that may help regulate the wake–sleep cycle. The gonads are the main source of sex hormones. In males, they are located in the scrotum. Male gonads, or testes, secrete hormones called androgens, the most important of which is testosterone.

These hormones regulate body changes associated with sexual development, including enlargement of the penis, the growth spurt that happens during puberty, and the appearance of other male secondary sex characteristics such as deepening of the voice , growth of facial and pubic hair, and the increase in muscle growth and strength. Working with hormones from the pituitary gland, testosterone also supports the production of sperm by the testes. The female gonads, the ovaries, are in the pelvis. They produce eggs and secrete the female hormones estrogen and progesterone. Estrogen is involved in the development of female sexual features such as breast growth, the build-up of body fat around the hips and thighs, and the growth spurt that happens during puberty. Both estrogen and progesterone are also involved in pregnancy and the regulation of the menstrual cycle . The Pancreas The pancreas produces (in addition to others) two important hormones, insulin and glucagon. They work together to maintain a steady level of glucose, or sugar, in the blood and to keep the body supplied with fuel to produce and maintain stores of energy.

previous continue What the Endocrine System Does Once a hormone is secreted, it travels from the endocrine gland through the bloodstream to target cells designed to receive its message. Along the way to the target cells, special proteins bind to some of the hormones. The special proteins act as carriers that control the amount of hormone that is available to interact with and affect the target cells. Also, the target cells have receptors that latch onto only specific hormones, and each hormone has its own receptor, so that each hormone will communicate only with specific target cells that possess receptors for that hormone. When the hormone reaches its target cell, it locks onto the cell's specific receptors and these hormone-receptor combinations transmit chemical instructions to the inner workings of the cell. When hormone levels reach a certain normal or necessary amount, further secretion is controlled by important body mechanisms to maintain that level of hormone in the blood. This regulation of hormone secretion may involve the hormone itself or another substance in the blood related to the hormone.

For example, if the thyroid gland has secreted adequate amounts of thyroid hormones into the blood, the pituitary gland senses the normal levels of thyroid hormone in the bloodstream and adjusts its release of thyrotropin, the pituitary hormone that stimulates the thyroid gland to produce thyroid hormones. Another example is parathyroid hormone, which increases the level of calcium in the blood. When the blood calcium level rises, the parathyroid glands sense the change and decrease their secretion of parathyroid hormone. This turnoff process is called a negative feedback system. previous continue Problems With the Endocrine System Too much or too little of any hormone can be harmful to the body. For example, if the pituitary gland produces too much growth hormone, a child may grow excessively tall. If it produces too little, a child may be abnormally short. Controlling the production of or replacing specific hormones can treat many endocrine disorders in children and adolescents, some of which include: Adrenal insufficiency. This condition is characterized by decreased function of the adrenal cortex and the consequent underproduction of adrenal corticosteroid hormones. The symptoms of adrenal insufficiency may include weakness, fatigue, abdominal pain, nausea, dehydration, and skin changes.

Doctors treat adrenal insufficiency by giving replacement corticosteroid hormones. Cushing syndrome. Excessive amounts of glucocorticoid hormones in the body can lead to Cushing syndrome. In children, it most often results when a child takes large doses of synthetic corticosteroid drugs (such as prednisone) to treat autoimmune diseases such as lupus. If the condition is due to a tumor in the pituitary gland that produces excessive amounts of corticotropin and stimulates the adrenals to overproduce corticosteroids, it's known as Cushing disease. Symptoms may take years to develop and include obesity, growth failure, muscle weakness, easy bruising of the skin, acne, high blood pressure, and psychological changes. Depending on the specific cause, doctors may treat this condition with surgery, radiation therapy, chemotherapy, or drugs that block the production of hormones. Type 1 diabetes . Previously known as juvenile diabetes, this condition happens when the pancreas doesn't produce enough insulin. In children and teens, it's usually the result of an autoimmune disorder in which specific immune system cells and antibodies produced by the immune system attack and destroy the cells of the pancreas that produce insulin.

Symptoms include excessive thirst, hunger, urination (peeing), and weight loss. Type 1 diabetes can cause long-term complications, including kidney problems, nerve damage, blindness, and early coronary heart disease and stroke. To control their blood sugar levels and reduce the risk of developing diabetes complications, kids need regular injections of insulin. Type 2 diabetes . Unlike type 1 diabetes, in which the body can't produce normal amounts of insulin, in type 2 diabetes the body can't respond to insulin normally. Children and teens who have it tend to be overweight, and it is believed that excess body fat plays a role in this insulin resistance. In fact, the rate of type 2 diabetes in kids has risen along with the dramatically increasing rates of obesity among kids. The symptoms and possible complications of type 2 diabetes are basically the same as those of type 1. Some kids and teens can control their blood sugar level with dietary changes, exercise, and oral medications, but many will need to take insulin injections like those with type 1 diabetes. Growth hormone problems. Too much growth hormone in children who are still growing will make their bones and other body parts grow excessively, resulting in gigantism.

This rare condition is usually caused by a pituitary tumor and can be treated by removing the tumor. In contrast, when the pituitary gland fails to produce adequate amounts of growth hormone, a child's growth in height is impaired. Hypoglycemia (low blood sugar) may also occur in kids with growth hormone deficiency, particularly in infants and young children with the condition. Hyperthyroidism. Hyperthyroidism is a condition in which the levels of thyroid hormones in the blood are excessively high. Symptoms may include weight loss, nervousness, tremors, excessive sweating, increased heart rate and blood pressure, protruding eyes, and a swelling in the neck from an enlarged thyroid gland (goiter). In kids this is usually caused by Graves' disease, an autoimmune disorder in which specific antibodies produced by the immune system stimulate the thyroid gland to become overactive. The disease may be controlled with medications or by removal or destruction of the thyroid gland through surgery or radiation treatments. Hypothyroidism. Hypothyroidism is when the levels of thyroid hormones in the blood are abnormally low.

Thyroid hormone deficiency slows body processes and may lead to fatigue, a slow heart rate, dry skin, weight gain, constipation, and, in kids, slowing of growth and delayed puberty. Hashimoto's thyroiditis, which results from an autoimmune process that damages the thyroid and blocks thyroid hormone production, is the most common cause of hypothyroidism in kids. Infants can also be born with an absent or underdeveloped thyroid gland, resulting in hypothyroidism. It can be treated with oral thyroid hormone replacement. Precocious puberty . Body changes associated with puberty may occur at an abnormally young age in some kids if the pituitary hormones that stimulate the gonads to produce sex hormones rise prematurely. An injectable medication is available that can suppress the secretion of these pituitary hormones (known as gonadotropins) and arrest the progression of sexual development in most of these children. Endocrine System Endocrine System El sistema endocrino Ever dozed through chemistry class and wondered what chemistry had to do with you? A lot! Your body produces its own chemicals and uses them to control certain functions, and the main system that coordinates these chemicals is called the endocrine system. What Is the Endocrine System?

Although we rarely think about the endocrine system, it influences almost every cell, organ, and function of our bodies. The endocrine system plays a role in regulating mood, growth and development, tissue function, metabolism, and sexual function and reproductive processes. In general, the endocrine system is in charge of body processes that happen slowly, such as cell growth. Faster processes like breathing and body movement are controlled by the nervous system. But even though the nervous system and endocrine system are separate systems, they often work together to help the body function properly. The foundations of the endocrine system are the hormones and glands. As the body's chemical messengers, hormones transfer information and instructions from one set of cells to another. Many different hormones move through the bloodstream, but each type of hormone is designed to affect only certain cells. A gland is a group of cells that produces and secretes, or gives off, chemicals. A gland selects and removes materials from the blood, processes them, and secretes the finished chemical product for use somewhere in the body. Some types of glands release their secretions in specific areas.

For instance, exocrine (pronounced: EK-suh-krin) glands, such as the sweat and salivary glands, release secretions in the skin or inside the mouth. Endocrine glands, on the other hand, release more than 20 major hormones directly into the bloodstream where they can be transported to cells in other parts of the body. The major glands that make up the human endocrine system include the: hypothalamus continue Hypothalamus The hypothalamus (pronounced: hi-po-THAL-uh-mus), a collection of specialized cells that is located in the lower central part of the brain, is the main link between the endocrine and nervous systems. Nerve cells in the hypothalamus control the pituitary gland by producing chemicals that either stimulate or suppress hormone secretions from the pituitary. Pituitary Although it is no bigger than a pea, the pituitary (pronounced: puh-TOO-uh-ter-ee) gland, located at the base of the brain just beneath the hypothalamus, is considered the most important part of the endocrine system.

It's often called the "master gland" because it makes hormones that control several other endocrine glands. The production and secretion of pituitary hormones can be influenced by factors such as emotions and changes in the seasons. To accomplish this, the hypothalamus provides information sensed by the brain (such as environmental temperature, light exposure patterns, and feelings) to the pituitary. The tiny pituitary is divided into two parts: the anterior lobe and the posterior lobe. The anterior lobe regulates the activity of the thyroid, adrenals, and reproductive glands.

The anterior lobe produces hormones such as: growth hormone, which stimulates the growth of bone and other body tissues and plays a role in the body's handling of nutrients and minerals prolactin (pronounced: pro-LAK-tin), which activates milk production in women who are breastfeeding thyrotropin (pronounced: thy-ruh-TRO-pin), which stimulates the thyroid gland to produce thyroid hormones corticotropin (pronounced: kor-tih-ko-TRO-pin), which stimulates the adrenal gland to produce certain hormones The pituitary also secretes endorphins (pronounced: en-DOR-fins), chemicals that act on the nervous system and reduce feelings of pain. In addition, the pituitary secretes hormones that signal the reproductive organs to make sex hormones. The pituitary gland also controls ovulation and the menstrual cycle in women. The posterior lobe of the pituitary releases antidiuretic (pronounced: an-ty-dy-uh-REH-tik) hormone, which helps control the balance of water in the body.

The posterior lobe also produces oxytocin (pronounced: ahk-see-TOE-sin), which triggers the contractions of the uterus in a woman having a baby. previous continue Thyroid The thyroid (pronounced: THY-royd), located in the front part of the lower neck, is shaped like a bow tie or butterfly and produces the thyroid hormones thyroxine (pronounced: thy-RAHK-sin) and triiodothyronine (pronounced: try-eye-oh-doe-THY-ruh-neen). These hormones control the rate at which cells burn fuels from food to produce energy. The production and release of thyroid hormones is controlled by thyrotropin (pronounced: thy-ruh-TRO-pin), which is secreted by the pituitary gland. The more thyroid hormone there is in a person's bloodstream, the faster chemical reactions occur in the body. Why are thyroid hormones so important? There are several reasons — for example, they help kids' and teens' bones grow and develop, and they also play a role in the development of the brain and nervous system in kids.

Parathyroids Attached to the thyroid are four tiny glands that function together called the parathyroids (pronounced: par-uh-THY-roydz). They release parathyroid hormone, which regulates the level of calcium in the blood with the help of calcitonin (pronounced: kal-suh-TOE-nin), which is produced in the thyroid. Adrenal Glands The body also has two triangular adrenal (pronounced: uh-DREE-nul) glands, one on top of each kidney. The adrenal glands have two parts, each of which produces a set of hormones and has a different function: The outer part, the adrenal cortex, produces hormones called corticosteroids (pronounced: kor-tih-ko-STER-oydz) that influence or regulate salt and water balance in the body, the body's response to stress, metabolism, the immune system, and sexual development and function. The inner part, the adrenal medulla (pronounced: muh-DUH-luh), produces catecholamines (pronounced: kah-tuh-KO-luh-meenz), such as epinephrine (pronounced: eh-puh-NEH-frun).

Also called adrenaline, epinephrine increases blood pressure and heart rate when the body experiences stress. previous continue Pineal The pineal (pronounced: pih-NEE-ul) body, also called the pineal gland, is located in the middle of the brain. It secretes melatonin (pronounced: meh-luh-TOE-nin), a hormone that may help regulate when you sleep at night and when you wake in the morning. Reproductive Glands The gonads are the main source of sex hormones. Most people don't realize it, but both guys and girls have gonads. In guys the male gonads, or testes (pronounced: TES-teez), are located in the scrotum. They secrete hormones called androgens (pronounced: AN-druh-junz), the most important of which is testosterone (pronounced: tess-TOSS-tuh-rone). These hormones tell a guy's body when it's time to make the changes associated with puberty , like penis and height growth, deepening voice, and growth in facial and pubic hair.

Working with hormones from the pituitary gland, testosterone also tells a guy's body when it's time to produce sperm in the testes. A girl's gonads, the ovaries (pronounced: OH-vuh-reez), are located in her pelvis. They produce eggs and secrete the female hormones estrogen (pronounced: ESS-truh-jen) and progesterone (pronounced: pro-JESS-tuh-rone). Estrogen is involved when a girl begins to go through puberty. During puberty, a girl will experience breast growth, will begin to accumulate body fat around the hips and thighs, and will have a growth spurt. Estrogen and progesterone are also involved in the regulation of a girl's menstrual cycle. These hormones also play a role in pregnancy. Although the endocrine glands are the body's main hormone producers, some other organs not in the endocrine system — such as the brain, heart, lungs, kidneys, liver, and skin — also produce and release hormones. Pancreas The pancreas (pronounced: PAN-kree-us) is also part of the body's hormone-secreting system, even though it is also associated with the digestive system because it produces and secretes digestive enzymes.

The pancreas produces (in addition to others) two important hormones, insulin (pronounced: IN-suh-lin) and glucagon (pronounced: GLOO-kuh-gawn). They work together to maintain a steady level of glucose, or sugar, in the blood and to keep the body supplied with fuel to produce and maintain stores of energy. previous continue What Does the Endocrine System Do? Once a hormone is secreted, it travels from the endocrine gland that produced it through the bloodstream to the cells designed to receive its message. These cells are called target cells. Along the way to the target cells, special proteins bind to some of the hormones. These proteins act as carriers that control the amount of hormone that is available for the cells to use. The target cells have receptors that latch onto only specific hormones, and each hormone has its own receptor, so that each hormone will communicate only with specific target cells that have receptors for that hormone. When the hormone reaches its target cell, it locks onto the cell's specific receptors and these hormone-receptor combinations transmit chemical instructions to the inner workings of the cell. When hormone levels reach a certain normal amount, the endocrine system helps the body to keep that level of hormone in the blood.

For example, if the thyroid gland has secreted the right amount of thyroid hormones into the blood, the pituitary gland senses the normal levels of thyroid hormone in the bloodstream. Then the pituitary gland adjusts its release of thyrotropin, the hormone that stimulates the thyroid gland to produce thyroid hormones. Another example of this process is parathyroid hormone, which increases the level of calcium in the blood. When the blood calcium level rises, the parathyroid glands sense the change and reduce their secretion of parathyroid hormone. This turnoff process is called a negative feedback system. previous continue Things That Can Go Wrong Too much or too little of any hormone can be harmful to your body. For example, if the pituitary gland produces too much growth hormone, a teen may grow excessively tall. If it produces too little, a teen may be unusually short. Doctors can often treat problems with the endocrine system by controlling the production of hormones or replacing certain hormones with medication. Endocrine problems that can affect teens include: Adrenal insufficiency. This condition occurs when the adrenal glands don't produce enough corticosteroids. The symptoms of adrenal insufficiency may include weakness, fatigue, abdominal pain, nausea, dehydration, and skin changes.

Doctors treat adrenal insufficiency with medications to replace corticosteroid hormones. Type 1 diabetes . When the pancreas fails to produce enough insulin, type 1 diabetes (previously known as juvenile diabetes) occurs. In kids and teens, type 1 diabetes is usually an autoimmune disorder, which means that some parts of the body's immune system attack and destroy the cells of the pancreas that produce insulin. To control their blood sugar levels and reduce the risk of developing diabetes problems, kids and teens with this condition need regular injections of insulin. Type 2 diabetes. Unlike type 1 diabetes, in which the body can't produce normal amounts of insulin, in type 2 diabetes the body can't respond to insulin normally. Kids and teens with the condition tend to be overweight. Some kids and teens can control their blood sugar level with dietary changes, exercise, and oral medications, but many will need to take insulin injections like people with type 1 diabetes. Growth hormone problems. Too much growth hormone in kids and teens who are still growing will make their bones and other body parts grow excessively. This rare condition (sometimes called gigantism) is usually caused by a pituitary tumor and can be treated by removing the tumor.

The opposite can happen when a kid or teen has a pituitary glad that doesn't produce enough growth hormone. Doctors may treat these growth problems with medication. Hyperthyroidism . Hyperthyroidism is a condition in which the levels of thyroid hormones in the blood are very high. In kids and teens, the condition is usually caused by Graves' disease, an immune system problem that causes the thyroid gland to become very active. Doctors may treat hyperthyroidism with medications, surgery, or radiation treatments. Hypothyroidism . Hypothyroidism is a condition in which the levels of thyroid hormones in the blood are very low. Thyroid hormone deficiency slows body processes and may lead to fatigue, a slow heart rate, dry skin, weight gain, and constipation. Kids and teens with this condition may also grow more slowly and reach puberty at a later age. Hashimoto's thyroiditis is an immune system problem that often causes problems with the thyroid and blocks the production of thyroid hormone. Doctors often treat this problem with medication. Precocious puberty. If the pituitary glands release hormones that stimulate the gonads to produce sex hormones too early, some kids may begin to go through puberty at a very young age.

This condition is called precocious puberty. Kids and teens who are affected by precocious puberty can be treated with medication that will help them develop at a normal rate. Cortisone | Article about cortisone by The Free Dictionary Cortisone | Article about cortisone by The Free Dictionary Related to cortisone: cortisol , prednisone cortisone (kôr`tĭsōn'), steroid hormone hormone, secretory substance carried from one gland or organ of the body via the bloodstream to more or less specific tissues, where it exerts some influence upon the metabolism of the target tissue. ..... Click the link for more information. whose main physiological effect is on carbohydrate metabolism. It is synthesized from cholesterol cholesterol , fatty lipid found in the body tissues and blood plasma of vertebrates; it is only sparingly soluble in water, but much more soluble in some organic solvents. A steroid, cholesterol can be found in large concentrations in the brain, spinal cord, and liver. ..... Click the link for more information. in the outer layer, or cortex, of the adrenal gland adrenal gland or suprarenal gland , endocrine gland (see endocrine system) about 2 in. (5.1 cm) long situated atop each kidney.

The outer yellowish layer (cortex) of the adrenal gland secretes about 30 steroid hormones, the most important of which are aldosterone and ..... Click the link for more information. under the stimulation of adrenocorticotropic hormone adrenocorticotropic hormone , polypeptide hormone secreted by the anterior pituitary gland. Its chief function is to stimulate the cortex of the adrenal gland to secrete adrenocortical steroids, chief among them cortisone. ..... Click the link for more information. (ACTH). Cortisone is classed as a glucocorticoid with cortisol cortisol or hydrocortisone, steroid hormone that in humans is the major circulating hormone of the cortex, or outer layer, of the adrenal gland. Like cortisone, cortisol is classed as a glucocorticoid; it stimulates liver glycogen formation while it decreases the rate ..... Click the link for more information. and corticosterone corticosterone , steroid hormone secreted by the outer layer, or cortex, of the adrenal gland. Classed as a glucocorticoid, corticosterone helps regulate the conversion of amino acids into carbohydrates and glycogen by the liver, and helps stimulate glycogen formation in the .....

Click the link for more information. ; its effects include increased glucose release from the liver, increased liver glycogen synthesis, and decreased utilization of glucose by the tissues. These actions tend to counter the effects of insulin insulin, hormone secreted by the β cells of the islets of Langerhans, specific groups of cells in the pancreas. Insufficiency of insulin in the body results in diabetes. Insulin was one of the first products to be manufactured using genetic engineering. ..... Click the link for more information. and may aggravate or mimic diabetes in sufficiently high doses. Cortisone also exerts an effect on salt retention in the kidneys similar to that of aldosterone aldosterone , steroid secreted by the cortex of the adrenal gland. It is the most potent hormone regulating the body's electrolyte balance. Aldosterone acts directly on the kidney to decrease the rate of sodium-ion excretion (with accompanying retention of water), and to ..... Click the link for more information. , although it is not as potent. The hormone causes increased breakdown of proteins and decreased protein synthesis, and large doses given over a long period of time may result in inhibited growth in children or weakening of bones and wasting of muscles in adults.

The principal medical use of cortisone comes from its anti-inflammatory and antiallergic effects; it is extremely useful in the treatment of innumerable diseases including asthma and other allergic reactions, arthritis, and various skin diseases. Cortisone is necessary to maintain life and enable the organism to respond to stress; failure of the adrenal glands to synthesize cortisone (Addison's disease) or surgical removal of the adrenals is fatal unless cortisone is given as replacement therapy. Although less cortisone is manufactured in the body than either cortisol or corticosterone and although cortisone is less potent than cortisol, the term cortisone is often used collectively to include the other glucocorticoids, both the naturally occurring and the synthetic compounds such as prednisone. Small quantities of cortisone were first isolated from animal adrenals in 1935–36. A method of manufacture, involving laboratory synthesis from an acid of bile bile, bitter alkaline fluid of a yellow, brown, or green color, secreted, in man, by the liver. Bile, or gall, is composed of water, bile acids and their salts, bile pigments, cholesterol, fatty acids, and inorganic salts.

..... Click the link for more information. , was developed, and in 1949 cortisone was first offered commercially. The specific mechanisms by which cortisone and similar compounds act are still poorly understood. Bibliography Histology-World! Histology Testbank-Endocrine 4a d. None of the above e. All of the above Answer: a The cells of the pars distalis (anterior pituitary) can be classified as acidophils or basophils depending on their affinity for acid or basic dyes, respectively. The acidophils are the somatotropic cells and the lactotropic cells. Thus, growth hormone and prolactin are secreted by acidophilic cells. The basophils are the gonadotropic cells, corticotropic cells and thyrotropic cells. The basophils are the gonadotropic cells, corticotropic cells and thyrotropic cells. Thus, the basophils secrete FSH, LH, ACTH, and TSH. Histology hint from Sarah Bellham: There are two mnemonics to use when thinking of acidophils and basophils of the anterior pituitary.

"GPA" (growth hormone and prolactin are secreted by the acidophils). "B-FLAT" (basophils secrete FSH, LH, ACTH, and TSH). 5. e. None of the above Answer: a The adrenal gland is composed of the adrenal cortex and the adrenal medulla. The layers of the adrenal cortex, from outermost to innermost are: zona glomerulosa, zona fasciculata, and zona reticularis. The respective principle products are: mineralocorticods, glucocorticoids, and sex steroids. The cells of the adrenal medulla are chromaffin cells. They secrete the catecholamines (epinephrine and norepinephrine). Histology hint from Sarah Bellham: A mnemonic to remember the layers of the adrenal cortex and their respective products is "Go Find Rex; Make Good Sex" (glomerulosa, fasciculata, reticularis) (mineralocorticoid, glucocorticoid, sex steroids). 10. What cell of the parathyroid gland is also called a "chief cell"? a.

Principal cell Adrenal corticosteroid | definition of adrenal corticosteroid by Medical dictionary Adrenal corticosteroid | definition of adrenal corticosteroid by Medical dictionary corticosteroid [kor″tĭ-ko-ster´oid] any of the hormones produced by the adrenal cortex ; also, their synthetic equivalents. Called also adrenocortical hormone and adrenocorticoid . All the hormones are steroids having similar chemical structures, but quite different physiologic effects. Generally they are divided into glucocorticoids ( cortisol , cortisone , and corticosterone ), mineralocorticoids ( aldosterone and desoxycorticosterone , and also corticosterone ) and androgens . Patients who must take exogenous adrenal corticosteroids to supplement a deficit in endogenous cortisol or as a treatment for metastatic breast cancer should be thoroughly instructed in self-medication. Their needs are somewhat similar to those of the insulin-dependent diabetic patient. They should know the prescribed dosage and basic therapeutic action of the oral corticosteroid preparation they are taking and should be aware of the importance of taking the medication at the same time every day. The medication should never be discontinued abruptly for any reason.

It is advisable that the patient carry an extra prescription when traveling, in case the supply is used up before returning home. These patients also need to wear some form of medical identification so that all health care professionals with whom they come in contact will know that they are receiving hormones of this kind. This includes dentists, oral surgeons, emergency department personnel, and others who might not be familiar with the patient's medical history. cor·ti·co·ste·roid (kōr'ti-kō-stĕr'oyd), Synonym(s): adrenocorticoid , corticoid (3) , cortin corticosteroid /cor·ti·co·ster·oid/ (-ster´oid) any of the steroids elaborated by the adrenal cortex (excluding the sex hormones) or any synthetic equivalents; divided into two major groups, the glucocorticoids and mineralocorticoids ; used clinically for hormonal replacement therapy, for suppression of ACTH secretion, as anti-inflammatory agents, and to suppress the immune response. corticosteroid (kôr′tĭ-kō-stĕr′oid′,-stîr′-) n.

Any of the steroid hormones produced by the adrenal cortex or their synthetic equivalents, including the glucocorticoids, such as cortisol, and the mineralocorticoids, such as aldosterone. Also called adrenocorticosteroid. corticosteroid [kôr′tikōstir′oid] Etymology: L, cortex + steros, solid any one of hormones elaborated by the adrenal cortex (excluding the sex hormones of adrenal origin) that influence or control key processes of the body. These processes include carbohydrate and protein metabolism, maintenance of serum glucose levels, electrolyte and water balance, and functions of the cardiovascular system, the skeletal muscle, the kidneys, and other organs. The corticosteroids synthesized by the adrenal glands include the glucocorticoids and the mineralocorticoids. The principal glucocorticoids are cortisol and corticosterone. The only physiologically important mineralocorticoid in humans is aldosterone. These hormones may be manufactured and administered exogenously. The glucocorticoids tend to cause the cells of the body to shift from carbohydrate catabolism to fat catabolism, to accelerate the breakdown of proteins to amino acids, and to help maintain normal blood pressure.

The secretion of these hormones increases during stress, especially that produced by anxiety and severe injury. Chronic overproduction of these substances is associated with various disorders, such as Cushing's syndrome. A high blood level of glucocorticoids markedly increases the number of eosinophils and decreases the size of lymphatic tissues, especially the thymus and the lymph nodes. The decrease in lymphocytes slows antibody formation and affects the body's immune system. Aldosterone is the most powerful of the natural mineralocorticoids in the regulation of electrolyte balance, especially in the balance of sodium and potassium. Cortisol induces sodium retention and potassium excretion, but less effectively than aldosterone. The effects of the corticosteroids on the cardiovascular system, which are not precisely understood, are most evident in hypocortisolism, when the reduction in blood volume, accompanied by increased viscosity, may cause hypotension and cardiovascular collapse. The absence of corticosteroids decreases capillary permeability, decreases vasomotor response of small vessels, and reduces cardiac size and output. The skeletal muscles require adequate amounts of corticosteroids to function normally; excessive amounts cause them to function abnormally.

Cortisol and its synthetic analogs can prevent or reduce inflammation by inhibiting edema, leukocytic migration, and disposition of collagen and by causing other complications associated with inflammatory processes. The antiinflammatory actions of synthetic hormones can be harmful, however, because they mask the disease process and prevent accurate observation of its progress. Hypoadrenalism may result from the too rapid withdrawal of such drugs after prolonged therapy. Toxic effects associated with prolonged large dose corticosteroid therapy include fluid and electrolyte imbalance, hyperglycemia and glycosuria, increased susceptibility to infections, myopathy, arrested growth, ecchymoses, Cushing's syndrome, acne, and behavioral disturbances. Myopathy, characterized by weakness of the proximal musculature of the arms and the legs and associated shoulder and pelvic muscles, may also develop. Corticosteroid therapy may also produce behavioral changes, such as schizophrenia, suicidal tendencies, nervousness, and insomnia. See also adrenal crisis .

corticosteroid Clinical pharmacology Any of the steroids elaborated by the adrenal cortex–excluding the sex hormones of adrenal origin in response to the release of ACTH by the pituitary gland, to any of their synthetic equivalents or to angiotensin II; corticosteroids are used to manage arthropathies, inflammation, CA cor·ti·co·ste·roid (kōr'ti-kō-ster'oyd) A steroid produced by the cortex of the suprarenal gland (i.e., adrenal corticoid); a corticoid containing a steroid. e.g.: Dermovate e.g.: Dermovate-NN Mild and moderate preparations have few side effects; Care is required in the use of potent or very potent topical corticosteroids and absorption through the skin can cause Cushingoid symptoms and adrenal cortex suppression; absorption is greatest through raw skin, or where larger areas of skin are treated. antiinflammatory drug A drug which inhibits or suppresses most inflammatory responses of an allergic, bacterial, traumatic or anaphylactic origin, as well as being immunosuppressant. They include the corticosteroids (e.g.

betamethasone, dexamethasone, fluorometholone, hydrocortisone acetate, loteprednol etabonate, prednisolone, rimexolone, triamcinolone). They are sometimes combined with an antibiotic drug (e.g. betamethasone combined with neomycin or sulfacetamide, dexamethasone combined with neomycin or polymyxin B). Corticosteroids have side effects, such as enhancing the activity of herpes simplex virus, fungal overgrowth, raising intraocular pressure or cataract formation.There are other antiinflammatory drugs that are non-steroidal (NSAID) and have little toxicity. They act mainly by blocking prostaglandin synthesis. These include diclofenac sodium, flurbiprofen sodium, indomethacin, ketorolac, nepafenac and oxyphenbutazone. See immunosuppressants ; steroid . cor·ti·co·ste·roid (kōr'ti-kō-ster'oyd)

Question: Which gland secretes the corticosteroids?
Answer: Adrenal